Cytop amorphous fluoropolymer

Perfluorinated dioxole monomers have been used to prepare a series of amorphous fluoropolymers such as Teflon AF and Hyflon AD. A third amorphous fluoropo-lymer, Cytop contains perfluorotetrahydrofuran and perfluorotetrahydropyran rings, but is prepared in a cyclopolymerization process from an acyclic monomer. These amorphous fluoropolymers retain the outstanding chemical, thermal, and surface properties associated with perfluorinated polymers while also having unique electrical, optical, and solubility characteristics. 

All three commercial amorphous fluoropolymers. Teflon AF, Hyflon AD, and Cytop posses a unique set of properties. All dissolve in fluorinated solvents and thus may be spin coated to produce thin hlms and coatings. The polymers may also be extruded and molded using traditional polymer processing techniques. Note that the polymers are not soluble in hydrocarbon solvents or water and retain the chemical and thermal stability of perfluorinated polymers such as Teflon . These polymers have lower density than the well-known semicrystalline perfluorinated polymers such as pTFE that results in lower refractive index, lower thermal conductivity, higher gas permeability, and lower dielectric constant. The polymers are transparent and have excellent mechanical properties below their Tg due to their amorphous character. The presence of a heterocyclic ring in the polymer backbone of these materials is key... 

Naritomi, M. Dec. 1996. CYTOP Amorphous Fluoropolymers for Low Loss POF Proc. POF-Asia-Pacific Forum, Tokyo. 

Naritomi, M., CYTOP amorphous fluoropolymers for low loss POP, Proc. POP-Asia Pacific Forum, Tokyo, December 1996. 

Two major families of amorphous fluoropolymers have been developed. Both rely on in-ehain rings to reduce aystaUinity in flie hcmopo er and in copotymers wifli a-olefins such as tetrafluoroefliylene and chlorotrifluoroethyl-ene. One incorporates 2,2-bis-trifluoromethyl-4,5-difluoro-1,3-dioxole (PDD) in copolymers with tetrafluoroethylene or chlorotrifluoroefc.ylene (TEFLON AF) and flie other is based oi monomas such as 5-oxaperfluoro-l,6-heptadiene, which when polymerized, produce the structure below (CYTOP ). Amorphous fluoropolymers are soluble in a... 

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